Control system and method for controlling dual fuel operation of industrial gas turbine power plants, preferably employing a digital computer

ABSTRACT

A gas turbine power plant is provided with an industrial gas turbine capable of sustained operation on either gas or liquid fuel, or a mixture of the two. One of more of such turbinegenerator plants are operated by a hybrid digital computer control system during all turbine operating modes. Optimum scheduling of either or both fuels under load is achieved by computer directed dual fuel subsystem operation. Computer determined fuel demands are continuously satisfied through either independent or simultaneous operation of the gas and liquid fuel subsystems.

United States Patent 91 Yannone et al.

CONTROL SYSTEM AND METHOD FOR CONTROLLING DUAL FUEL OPERATION OFINDUSTRIAL GAS TURBINE POWER PLANTS, PREFERABLY EMPLOYING A DIGITALCOMPUTER Inventors: Robert A. Yannone, Alden; Roy W.

Kiscaden, Springfield, both of Pa.

Assignee: Westinghouse Electrical Corporation, Pittsburgh, Pa.

Filed: Nov. 29, 1972 Appl. No.: 310,520

Related US Application Data Continuation of Ser. No. 205,261, Dec. 6,1971,

abandoned.

Int. Cl. H02p 9/04 Field of Search 290/2, 40,402; 322/14, 322/15, 28,33, 34, 3s, 59; 235/15121; 60/39.l4, 39.23 R

References Cited UNITED STATES PATENTS French 60/3928 COMBUSTOR PRESSURESENSOR BLADE PATH T VIBRATION EX TT DISC CAVITY T CONSOLE V SENSORS TSENSORS FROM PLANT 8 FROM PLANT B 1 Feb. 11, 1975 3,400,374 9/l968Schumann 235/l8l.l 3,435,326 5/1969 Zechlin 322/25 3,469,395 6/1969Spitsbergen et al. 60/3928 3,482,396 12/1969 Nelson et al (JO/39.283,588,265 6/1971 Berry 290/40 3,606,754 9/1971 White 60/39.]4

Primary Examiner-Glen Simmons Attorney, Agent, or FirmS. A. Seinberg[57] ABSTRACT A gas turbine power plant is provided with an industrialgas turbine capable of sustained operation on either gas or liquid fuel,or a mixture of the two. One of more of such turbine-generator plantsare operated by a hybrid digital computer control system during allturbine operating modes, Optimum scheduling of either or both fuelsunder load is achieved by computer directed dual fuel subsystemoperation. Computer determined fuel demands are continuously satisfiedthrough either independent or simultaneous operation of the gas andliquid fuel subsystems.

13 Claims, 41 Drawing Figures SPEED CONTROL 263 OUTPUT S YSTEM CENTRALPRINTER POWER FOR CONTROL a DEVICES 312 LOG .PATENTEDFEBI H975 1866.108

. sum Uuur 33 PATENIEI) FEB] 1 I975 SHEET 120! 33 TIME DESIRED VAL ESETTER GAS L TRANSFER '2 CONTROL SIGNAL OUTPUTV.D.C.

mums]--------------------------- O 6 N Smfmdzgm 2w om TE) N) I07 R04 DUM m5 m w m( V 2 I 3 CONTROL SIGNAL OUTPUT-V0.0.

PATENTED FEB] 1 I975 3.865.108 SHEET 13 0F 33 VARS GEN. FREQ D.C.FL'D.D.C. FLD. RUN BUS INC. GEN. TEMP AMPS. VOLT -voLT voLT 52G 52G E g gkg-JQQ GEN. BKR. GENBKR. 8% TRIP cLosE CLOSE LOAD LOAD 1332MB iB R MA L"K525i SYSTEM A E E vE RASE LOWER START sTART sTART R S R 7 a 9 10 II I213 I4 I5 l6 FIG. |6A I VOLT voLT REG. REG.

RAISE LowER MANUEL AUTO.

OFF

52L 52L ON SYNC. LINE LINE SYNC.

OFF BKR. BKR. ON A TRIP CLOSE Is I9 20 2| 23 24 2s 26 27 2s 29 soTURBINE TURBINE READY MAsTER AUX. To LUBE TURNING LUBE AUX. TRIP ToCONTROL PUMP PRESS GEAR PREss RESET RESET sTART -ON ON 63 PM ON 63 PsI aPATENTED Y 3,866,108

' SHEET l 0F 33 2O l l AUTO MANUEL SYNC. SYNC. SYNC. SYNC. LIGHT LIGHTFIG I68 I I SELECT SELECT lNDlC. DEV.

HOLD so 22 5e 3| 7 32 33 34 s1 e2 s3 s4 START as as FLAME FLAME STARTDEVICE TRIP TRIP L FUEL COMB. COMB. DEV. ON vALvE PRESS ON 6 7 OFFPATENTED 581 1 Ms sum 15 or 33 VOLTS AMPS FUEL DISC EXHA BLADE OONT. CAVTEMP. TEMP TURBINE TURBINE NORMAL EMERG. sTO START TURBINE A ALARM $5,;SHUT- HORN ALARM LAMP ALARM DOWN SILENCE REsET TEST I ALARM 45 46 T 4?4s 49 5O 52 55 54 55 GAS OIL FIG. l6C GAS OIL FUEL & I FUEL FUEL LOW GASONLY ONLY PRES. M'X

TRANsF.

' GAS TURB LOCAL REMOTE TsAg sF DEMAND EMERGENCY 1 OONTROL CONTROL R 8REVIEW NORMAL STOP AUX 4| 'BLEED .GEN. PUMP FLD. vALvE gg BKR. OFF BKR.CLOSED 52 G.

RESIDENT I SEQUENCING DATA TABLES i (7IO A e c o I PROCESS Raw:

l 7|4 RESIDENT LOCAL CONTROL A B c 0 TURBINE CONTROL DATA TABLES CONTROLDATA AREA POST- PROCESS FIG. 22 i fi ,624 626 2'. ANALOG INPUTS I STOREN we sToREo DATA 3. TURBINE TABLE MASTER LOGIC To EvALuATE o. RESIDENTTABLE SEQUENCE LOGIC b. OPERATOR PANEL INPUTS 628 SAVE 630 s32 OUTPUTRESIDENT- LAST cco s TURBINE TURBINE TABLE F PAIENTEI] FEBI H975 SHEET180F 33 LOGIC TABLE MASTER PRE- PROCESSOR Ill-I LOGIC PROGRAM Illl CCI'SANA LOGS I I I TURB. A RESIDENT TABLE READ ONLY I I I was 8 RESIDENTTABLE READ ONLY TURB. C RESIDENT TABLE READ ONLY TABLE TURB D RESIDENTRE AD ONLY POST- PROCESSOR R s O M A MW R Tm PPR O P FIG. l9

1. A gas turbine electric power plant comprising a gas turbine having acompressor and combustion and turbine elements, a generator having afield winding and being coupled to said turbine for drive power, a fuelsystem having plural subsystems for supplying one or more fuels to thegas tubrine combustion element, means for exciting said generator fieldwinding, a control system including a digital computer and aninput/output system therefor, a plurality of sensors disposed to monitorselected turbine parameters, said plurality of sensors comprising atleast an arrangemnt of fuel pressure sensors, said plurality of sensorsproviding control system inputs representative of said turbineparameters, means for selectively operating one or more of said pluralfuel subsystems to energize said turbine, and for controlling saidexciting means, and means for operating said computer to make controlaction determinations for implementation by said plural fuel subsystemoperating means and said exciting control means, said fuel systemcontrol actions being determined in response to time varyingcombinations of said sensors inputs, each of said combinationscomprising at least an input from said fuel pressure sensors.
 2. Anelectric power plant as set forth in claim 1 wherein said computeroperating means operates to determine control actions for simultaneousimplementation by said plural fuel subsystems operating means tomaintain gas turbine operation over a predefined range of exhausttemperatures, over at least one interval of gas turbine operation.
 3. Anelectric power plant as set forth in claim 1 wherein means are providedfor detecting generator load and said computer operating means furtherprovides for controlling said plural fuel subsystem operating meAns inresponse to detected load to regulate the generator loads substantiallyto a predetermined value.
 4. An electric power plant as set forth inclaim 2 wherein means ary provided for detecting generator load and saidcomputer operating means further provides for controlling said pluralfuel subsystem operating means in response to detected load to regulatethe generator load substantially to a predetermined value.
 5. Anelectric power plant as set forth in claim 1 wherein said computeroperating means operates to determine control actions for implementationby one of said plural fuel subsystems operating means in response to aninput from said fuel pressure sensors indicating a deficiency of fuelsupply to another of said plural fuel subsystems.
 6. An electric powerplant as set forth in claim 2 wherein said computer operating meansfurther operates to determine control actions for implementation by oneof said plural fuel subsystems operating means in response to an inputfrom said fuel pressure sensors indicating a deficiency of fuel supplyto another of said plural fuel subsystems.
 7. An electric power plant asset forth in claim 5 wherein means are provided for detecting generatorload and said computer operating means further provides for controllingsaid plural fuel subsystems operating means in response to detected loadto regulate the generator load substantially to a predetermined value.8. An electric power plant as set forth in claim 6 wherein means areprovided for detecting generator load and said computer operating meansfurther provides for controlling said plural fuel subsystems operatingmeans in response to detected load to regulate the generator loadsubstantially to a predetermined value.
 9. An electric power plant asset forth in claim 1 wherein said computer operating means operates todetermine control actions for implementation by one of said plural fuelsubsystem operating means over a first interval of operation of said gasturbine and on the occurrence of one or more predefined events, furtheroperates to determine control actions for implementation by another ofsaid plural fuel subsystem operating means over a second interval ofoperation of said gas turbine.
 10. an electric power plant as set forthin claim 2 wherein said computer operating means further operates todetermine control actions for a simultaneous implementation by saidplural fuel subsystem operating means to maintain gas turbine operationover a predefined range of turbine exhaust temperatures, over a thirdinterval of operation of said gas turbine, intermediate said first andsecond intervals.
 11. An electric power plant as set forth in claim 10wherein means are provided for detecting generator load and saidcomputer operating means further provides for controlling said pluralfuel subsystem operating means in response to detected load to regulatethe generator load substantially to a predetermined value.
 12. Anelectric power plant as set forth in claim 10 wherein said computeroperating means further operates to vary the duration of said thirdinterval in a manner functionally related to said turbine exhausttemperature.
 13. An electric power plant as set forth in claim 11wherein said computer operating means further operates to vary theduration of said third interval in a manner functionally related to saidturbine exhaust temperatures.